Honeywell SPZ-8000 - Flight Level Change Mode

SPZ--8000 Digital Integrated Flight Control System
A28--1146--055
REV 2
Modes of Operation
8-42
When the vertical speed reference is changed using the pitch wheel, the
advisory display indicates the commanded vertical speed reference.
The VSI displays actual aircraft vertical speed. Selecting vertical speed
resets all previously selected vertical modes. The following actions
cancel the vertical speed mode:
D Pushing the VS button
D Selecting another vertical mode
D Selecting go--around
D Selecting standby.
FLIGHT LEVEL CHANGE MODE
Pushing the FLC button on the flight guidance controller selects the
airspeed hold mode and overrides all active pitch flight director modes,
except VNAV. When VNAV is engaged, pushing the FLC button on the
flight guidance controller selects the VNAV submode vertical flight level
change (VFLC). The IAS/Mach reference bug on the EADI is
synchronized to the existing IAS/Mach when the mode is engaged.
When a new reference is selected using the IAS/Mach reference knob
on the remote instrument controller, the system flies the new reference.
The IAS/Mach speed target comes from the coupled EADI. The system
flies the IAS or Mach bug reference, whichever is selected by the
instrument remote controller. If t he system is switched from IAS to
Mach (or Mach to IAS), the reference bug does not move, only the
digital readout on the EADI is changed. There is no change to the
aircraft configuration when the switch is made.
The FLC mode is basically an airspeed mode. However, it differs from
a standard IAS or Mach mode in the following aspects:
D Although the FLC mode, in the long term, tracks the speed reference
bug, short--term emphasis is on vertical speed. This minimizes
vertical speed excursions due to disturbances or large airspeed
changes.
D The FLC mode is set up to change the flight level from present
altitude to the preselected altitude. The system tries to prevent flying
away from the preselected altitude target. For example, if the throttle
is retarded during a climb toward a preselected altitude target, the
system tries to maintain a positive vertical speed and therefore it
decelerates rather than descends after the vertical speed reaches
zero.